Source/charon/payloads/nonce_payload.c

   1 /**
   2  * @file nonce_payload.h
   3  *
   4  * @brief Declaration of the class nonce_payload_t.
   5  *
   6  * An object of this type represents an IKEv2 Nonce-Payload.
   7  *
   8  */
   9
  10 /*
  11  * Copyright (C) 2005 Jan Hutter, Martin Willi
  12  * Hochschule fuer Technik Rapperswil
  13  *
  14  * This program is free software; you can redistribute it and/or modify it
  15  * under the terms of the GNU General Public License as published by the
  16  * Free Software Foundation; either version 2 of the License, or (at your
  17  * option) any later version.  See <http://www.fsf.org/copyleft/gpl.txt>.
  18  *
  19  * This program is distributed in the hope that it will be useful, but
  20  * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  21  * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  22  * for more details.
  23  */
  24
  25 /* offsetof macro */
  26 #include <stddef.h>
  27
  28 #include "nonce_payload.h"
  29
  30 #include "encodings.h"
  31 #include "../utils/allocator.h"
  32
  33
  34
  35 /**
  36  * Private data of an nonce_payload_t' Object
  37  *
  38  */
  39 typedef struct private_nonce_payload_s private_nonce_payload_t;
  40
  41 struct private_nonce_payload_s {
  42         /**
  43          * public nonce_payload_t interface
  44          */
  45         nonce_payload_t public;
  46
  47         /**
  48          * next payload type
  49          */
  50         u_int8_t  next_payload;
  51
  52         /**
  53          * Critical flag
  54          */
  55         bool critical;
  56
  57         /**
  58          * Length of this payload
  59          */
  60         u_int16_t payload_length;
  61
  62         /**
  63          * the contained nonce value
  64          */
  65         chunk_t nonce;
  66
  67         /**
  68          * @brief Computes the length of this payload.
  69          *
  70          * @param this  calling private_nonce_payload_t object
  71          * @return
  72          *                              SUCCESS in any case
  73          */
  74         status_t (*compute_length) (private_nonce_payload_t *this);
  75 };
  76
  77 /**
  78  * Encoding rules to parse or generate a nonce payload
  79  *
  80  * The defined offsets are the positions in a object of type
  81  * private_nonce_payload_t.
  82  *
  83  */
  84 encoding_rule_t nonce_payload_encodings[] = {
  85         /* 1 Byte next payload type, stored in the field next_payload */
  86         { U_INT_8,                      offsetof(private_nonce_payload_t, next_payload)         },
  87         /* the critical bit */
  88         { FLAG,                         offsetof(private_nonce_payload_t, critical)             },
  89         /* 7 Bit reserved bits, nowhere stored */
  90         { RESERVED_BIT, 0                                                                                                               },
  91         { RESERVED_BIT, 0                                                                                                               },
  92         { RESERVED_BIT, 0                                                                                                               },
  93         { RESERVED_BIT, 0                                                                                                               },
  94         { RESERVED_BIT, 0                                                                                                               },
  95         { RESERVED_BIT, 0                                                                                                               },
  96         { RESERVED_BIT, 0                                                                                                               },
  97         /* Length of the whole nonce payload*/
  98         { PAYLOAD_LENGTH,       offsetof(private_nonce_payload_t, payload_length)       },
  99         /* some nonce bytes, lenth is defined in PAYLOAD_LENGTH */
 100         { NONCE_DATA,                   offsetof(private_nonce_payload_t, nonce)                }
 101 };
 102
 103 /**
 104  * Implements payload_t's and nonce_payload_t's destroy function.
 105  * See #payload_s.destroy or nonce_payload_s.destroy for description.
 106  */
 107 static status_t destroy(private_nonce_payload_t *this)
 108 {
 109         if (this->nonce.ptr != NULL)
 110         {
 111                 allocator_free(this->nonce.ptr);
 112         }
 113         allocator_free(this);
 114
 115         return SUCCESS;
 116 }
 117
 118 /**
 119  * Implements nonce_payload_t's set_nonce function.
 120  * See #nonce_payload_t.set_nonce for description.
 121  */
 122 static status_t set_nonce(private_nonce_payload_t *this, chunk_t nonce)
 123 {
 124         if (nonce.len >= 16 && nonce.len <= 256)
 125         {
 126                 this->nonce.len = nonce.len;
 127                 this->nonce.ptr = nonce.ptr;
 128                 this->payload_length = NONCE_PAYLOAD_HEADER_LENGTH + nonce.len;
 129                 return SUCCESS;
 130         }
 131         return INVALID_ARG;
 132 }
 133
 134 /**
 135  * Implements nonce_payload_t's get_nonce function.
 136  * See #nonce_payload_t.get_nonce for description.
 137  */
 138 static status_t get_nonce(private_nonce_payload_t *this, chunk_t *nonce)
 139 {
 140         nonce->len = this->nonce.len;
 141         nonce->ptr = this->nonce.ptr;
 142         return SUCCESS;
 143 }
 144
 145 /**
 146  * Implements payload_t's get_encoding_rules function.
 147  * See #payload_s.get_encoding_rules for description.
 148  */
 149 static status_t get_encoding_rules(private_nonce_payload_t *this, encoding_rule_t **rules, size_t *rule_count)
 150 {
 151         *rules = nonce_payload_encodings;
 152         *rule_count = sizeof(nonce_payload_encodings) / sizeof(encoding_rule_t);
 153
 154         return SUCCESS;
 155 }
 156
 157 /**
 158  * Implements payload_t's get_type function.
 159  * See #payload_s.get_type for description.
 160  */
 161 static payload_type_t get_type(private_nonce_payload_t *this)
 162 {
 163         return NONCE;
 164 }
 165
 166 /**
 167  * Implements payload_t's get_next_type function.
 168  * See #payload_s.get_next_type for description.
 169  */
 170 static payload_type_t get_next_type(private_nonce_payload_t *this)
 171 {
 172         return (this->next_payload);
 173 }
 174
 175 /**
 176  * Implements payload_t's set_next_type function.
 177  * See #payload_s.set_next_type for description.
 178  */
 179 static status_t set_next_type(private_nonce_payload_t *this,payload_type_t type)
 180 {
 181         this->next_payload = type;
 182         return SUCCESS;
 183 }
 184
 185 /**
 186  * Implements payload_t's get_length function.
 187  * See #payload_s.get_length for description.
 188  */
 189 static size_t get_length(private_nonce_payload_t *this)
 190 {
 191         this->compute_length(this);
 192         return this->payload_length;
 193 }
 194
 195 /*
 196  * Described in header
 197  */
 198 nonce_payload_t *nonce_payload_create()
 199 {
 200         private_nonce_payload_t *this = allocator_alloc_thing(private_nonce_payload_t);
 201         if (this == NULL)
 202         {
 203                 return NULL;
 204         }
 205
 206         this->public.payload_interface.get_encoding_rules = (status_t (*) (payload_t *, encoding_rule_t **, size_t *) ) get_encoding_rules;
 207         this->public.payload_interface.get_length = (size_t (*) (payload_t *)) get_length;
 208         this->public.payload_interface.get_next_type = (payload_type_t (*) (payload_t *)) get_next_type;
 209         this->public.payload_interface.set_next_type = (status_t (*) (payload_t *,payload_type_t)) set_next_type;
 210         this->public.payload_interface.get_type = (payload_type_t (*) (payload_t *)) get_type;
 211         this->public.payload_interface.destroy = (status_t (*) (payload_t *))destroy;
 212         this->public.destroy = (status_t (*) (nonce_payload_t *)) destroy;
 213         this->public.set_nonce = (status_t (*) (nonce_payload_t *,chunk_t)) set_nonce;
 214         this->public.get_nonce = (status_t (*) (nonce_payload_t *,chunk_t*)) get_nonce;
 215
 216         this->critical = FALSE;
 217         this->next_payload = NO_PAYLOAD;
 218         this->payload_length = NONCE_PAYLOAD_HEADER_LENGTH;
 219         this->nonce.ptr = NULL;
 220         this->nonce.len = 0;
 221
 222         return (&(this->public));
 223 }
 224
 225